Micrometer



J. E. HASTINGS.

MICROMETER. APPLICATION FIVLED lULYII, 1919.

1, 348,87 5. Pa en ed Aug- 10, 1920.

UNITED STATES PATENT OFFICE.

JAMES E. HASTINGS, OF ATHOL, MASSACHUSETTS.

MIGROMETER.

Be it known that I, Janus E. IIASTINGS, a citizen of the United States, residing at -Athol, in the county of IVorcester and State of Massachusetts, have invented certain new and useful Improvements in Micrometers, of which the following is a specification.

This invention relates to new and useful improvements in micrometers, and more particularly to means for looking or providing a braking action for the spindle of the micrometer.

An important object of the invention is the provision of such a locking means which will not mar the surface of the spindle.

Another object isto provide such a locking means which is sensitive in its action, that is to say, the braking effect applied by the locking means can be regulated to suit the wishes of the operator and which is quick acting in its release.

A still further object is to provide such a locking means which is durable and which does not injure the general appearance of the tool to which it is applied.

Other objects and advantages of the invention will be apparent during the course of the following description. v v

In the accompanying drawings forming a part of this specification, and in which like numerals are employed to designate like parts throughout the same:

Figure 1 is a side elevation of a micrometer, embodying my invention;

Fig. 2 is a section on line 2-2 of Fig. 1-;

Fig. 3 is a longitudinal section enlarged for the purpose of clearness;

Fig. 4 is a section, taken on line 4& of Fig. 3;

Fig. 5 is a section on line 5-5 of Fig. 3;

Fig. 6 is an end elevation of the micrometer frame, showing the bushing inserted therein; and

Fig. 7 is a perspective view, showing the lugs on the bushing. I

Referring now more particularly to the drawings, the numeral 10 indicates the micrometer frame having the usual spindleeasing 11. At the inner end of the spindle casing the frame is provided with a recess 12 for a purpose hereinafter to appear.

' The spindle casing embodies a bushing 15 and is provided at its inner end witha bore 13 adapted to receive the shoulder 14 thereof, this bushing having a central bore adapted to receive the spindle of the micrometer.

Specification of Letters Patent. Patented Aug, 10, 1920.

1919. Serial No. 310,232.

The bushing 15 has a driving fit in the easlng and consequently is rigidly connected therewith. If desired the bushing may be mechanically secured to the casing in addition to the driving fit or may be formed integrally with the casing. It will therefore be seen that the bushing 15 is, in effect, an integral part of the casing 11. Formed upon the end of the bushing 15 is a post 16 having formed therein a groove 16 and a post 17 diametrically opposite the post 16 having formed thereon a lug 17 a spaced from the central bore of the bushing a distance corresponding to the depth of the notch or groove 16. By referring to Fig. 6, it will be seen that the outer surfaces of the posts 16 and 17 are arranged concentrically with the bore of the bushing and their inner surfaces are arranged eccentrically to said bore.

A knurled nut or operating ring 18 is provided having a central bore 19 which extends nearly but not entirely through the ring, thereby forming a shoulder 20 on the end thereof. The diameter of the bore is greater than the distance from the outside of the post 16 to the outside of the lug 17 of the post 17. A pair of similar eccentric washers 21"are provided, these washers having at one side a slot 22 formed therein and on the other side diametrically opposite the slot 22 a recess 23. By referring to Fig. 5 it will be seen that therecess 23 loosely receivesthe post 17 and the slot 22 receives the post 16.

Intermediate these washers is placed a cam washer 25 having an extension 26provided with a high point 27. By referring to Fig. 4, it will be seen that when the spindle is in place within the washer 25, the enlargement 26 thereof enters a groove 21 formed in the knurled ring 18. 3 i

In assembling the locking nut, one of the washers 21 is placed in position upon the posts16 and 17 as shown in Fig. 5. Eccentric washer 25 is then placed between these posts and the second of the washers 21 placed in position upon the post. The nut or knurled ring is then placedin position, the washer 20 being provided to exclude dirt, etc, from the interior. of the nut. Washer 25 is now moved so that its opening alines with the openings in the washers 21. By referring to Figs. 3 and 4, it will be seen that the reduced eccentric portion now enters the groove 16 of the post 16 and the knurled ring is now locked in place as the groove 21 post 17 and by the extension 26 of the washer 25. From the foregoing it will be obvious that when the spindle is placed in position, thus preventing the washer 25 from moving so that its extension 26 is removed from the groove, the ring 18 is locked in position in therecess 12.

Points 24 on eccentric washers 21' are high points and point 27 on eccentric washer 25 is the high point. .W hen the operating ring 18 is turned in a direction opposite to that indicated by the arrow on Fig. 4: the eccentric washer 25 moves also until the straight stop face 27 at point 27 touches post 16. Then these three high points coincide and the friction on the spindle is released and it is free. When it is desired to lock the spindle a movement is made as indicated by the arrow at 26. The ring 18 engages the high point 27 on ring 25 and the'na-tural tendency of the high point 27 is to move away from points 24 on the rings 21'. As

the circumferences of washers 21 are eccentric to the bore thereof and the inside diameter of ring 18 is the same as the out side diameter of washers 21', the ring 18 has to revolve in a correspondingly eccentric path on the surfaces of the washers. As

point 2% on the washers 21 is high'all other points must be less. It can be readily seen that'as the washer 25 is moved the point 27 gradually moves into less space and itnaturally crowds between the inside of the ring 18 and the surface of the spindle and causes a friction on sam e, while at the same time at a point directly opposite to point 27 there is a crowding pressure on each of the washers 21 against the-spindle.

It' will bereadily seen that if pressure is still applied to the ring 18 the distance between the high point on the cam washer and those on the eccentric washers naturally increases and as the diameter of ring 18 is constant thewashersj21 have to bind more tightly .onto'the spindle and hence the degree of friction is determined by the pressure applied. There are now three points 1 of contact on the spindle lying in different planes; the plane of one point being between the planes of the other two points and the actual contact ofthe-first named'point being upon the opposite side of the spindle from the contact points of the latter. The fact that the friction points are opposite causes v the operating ring to stay locked until released even though the spindle may be turned. When it is desired to release the spindle the ring718 is turned in a reverse direction causing the high point 27 on washer 25 to move-back until it touches post 16, when all high points ofthe washers coin cide and the spindle is freed, as previously described, y l 1WhileI have shown the operating nut or ring 18 and associated parts as being placed upon the upper end of the frame it will be obvious to those skilled in the art that this nut might be applied to the spindle at any desired point as for instance by placing the nut in the slot formed in the frame. 7

It is to be understood that the form of my invention herewith shown and described is to be taken as the preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subj oined claims.

Having thus described my invention, I claim: V

1. In a micrometer gage, the combination with a spindle casing having the usual bore, of posts carried by the casing and arranged upon opposite sides of said bore, an eccentric washer having an extension provided with a high point mounted intermediate said posts, a ring having an annular groove therein arranged about said posts, the ex- 7 tension of said eccentriowasher engaging in the groove of said ring when the bore of said washer is alined with thebore of said spindle casing.

2. In a micrometer gage, the combination with a spindle casing having the usual bore, of a pair of posts carried by the casing and arranged upon opposite sides of said bore, a lug formed on the outer face of one of said posts, an eccentric washer having an extension provided with a high point mounted intermediate said posts, a ring having an annular groove therein arranged about said posts, the extension of said eccentric washer engaging inthe groove of said ring when the bore of said washer is alined with the bore of said spindle casing, said lug being adapted to, enter the groove in said ring when said ring is arranged concentrically with the bore of said spindle casing.

3. In a micrometer gage, the combination with a spindle casing having the usual bore, of a pair of posts carried by the casing and arranged upon opposite sides of said here, a lug formed on the outer, face of one of said posts, an eccentric washer having an extensionprovided with a high point'mounted intermediate said posts, a ring having an annular groove therein arranged about said posts, the extension of said eccentric washer engaging in the groove ofsaid ringw-hen the bore of said washer is alined with the bore of said spindle casing, the lug on said post being adapted to enter the groove in said ring when the ring is arranged concentrically with the bore of said spindle casing, and means for holding said. ring in concentric relationto the bore of'said spindle casing. V

at. In a micrometer gage, the combination of a pair of posts carried by the casing and arranged upon opposite sides of said bore, a lug formed on the outer-face of one of saidposts, an eccentric wash r having-an extension provided with a high point mounted intermediate said posts, a, ring havingan annular groove therein arranged about said posts, the bore of said ring being greater than the distance from outside to outside oi said posts, the extension of said eccentric washer engaging in the groove of said ring, when the bore of said washer is alined with the bore of said spindle casing, said lug being adapted to enter the groove in said ring when said ring is arranged concentrically with the bore of said spindle casing, and means for holding said ring in con centric relation with the bore 01. said spindle casing comprising a washer mounted upon said post and slidably fitting the bore of said ring.

5. In a micrometer gage, the combination with a spindle casing having the usual bore, of a pair of posts carried by the casing and arranged upon opposite sides of said bore, a lug formed on the outer face of one of said posts, an eccentric washer having an extension provided with a high point mounted intermediate said posts, a ring having an annular groove therein arranged about said posts, the bore of said ring being greater than the distance from outside to outside of said posts, the extension of said eccentric washer engaging in the groove of said ring when the bore of said washer is alined with the bore of said spindle casing, said lug being adapted to enter the groove in said ring when said ring is arranged concentrically with the bore of said spindle casing, and means for holding said ring in concentric relation with the bore of said spindle casing comprising a washer mounted upon said post and slidably fitting the bore of said ring, the bore of said washer being slightly eccentric to the periphery thereof.

(3. In a micrometer gage, the combination with a spindle casing having the usual bore adapted to receive the spindle of the gage, of a pair of posts carried by said casing and arranged upon opposite sides of said bore the outer sides of said posts being concentric with said bore and the inner sides of said posts being eccentric with said bore, a lug formed on the outer face of one of said posts, and a groove formed in the inner face of the other of said posts, an eccentric washer arranged intermediate said posts and entering said groove, a ring having a central bore, the diameter of which is greater than the distance between the outside faces of said posts arranged about said posts, an annular groove formed in the interior of said ring, an extension on said eccentric washer adapted to enter said groove when the bore of the washer is alined with the bore of said spindle casing, the lug of said first-mentioned post being adapted to enin' the groove in said ring when said ring is arranged concentrically with the bore of said spindle casing, means for holding rin in approximately concentric relation with the bor of said spindle casing, and means operated by the rotation of said ring for shifting said washer.

1. 111a micrometer gage, the combination with a spindle casing having a bushing mounted therein provided with a central bore adapted to receive the spindle of the gage, of a pair of posts carried by said bushing, and arranged upon opposite sides of said bore, the outer sides of said posts be ing concentric with said bore and the inner sides of said posts being eccentric with said bore, a lug formed on the outer face of one of said posts, a groove formed in the inner "face of the other of said posts, an eccentric we lie'r arranged intermediate said posts and entering said groove, a ring having a central bore the diameter of which is greater than the distance between the outside face of said last-mentioned post and the outer side of the lug formed on said first mentioned post arranged about said posts,

an annular groove formed in the interior of said ring, an extension on said eccentric washer adapted to enter the groove in said ring when the bore of the washer is alined with the bore of said spindle casing, the lug of said first-mentioned postbeing adapted to engage in the groove in said ring when said ring is arranged concentrically with the bore of said spindle casing, means for holding said ring in approximate concentric relation with the bore of said spindle casing, and means operated by the rotation of said ring for shifting said eccentric washer.

8. In a micrometer gage, the combination with a spindle casing having the usual bore adapted to receive the spindle ot' the gage, of a pair of posts carried by the 'asing and arranged upon opposite sides of said bore, the outer sides of said posts being concentric with said bore and the innersides of said posts being eccentric with said bore, a lug formed on the outer face of one of said posts, and a groove formed in the inner face of the other of said posts, a pair of washers mounted upon said posts, an eccentric washer mounted intermediate said washers and between said posts, a ring having a central bore arranged about said post, an annular groove formed in the interior of said ring, an extension of said eccentric washer adapted to enter said groove when the bore of the washer is alined with the bore of said spindle casing, the lug of said first mentioned post being adapted to engage in the groove of said ring when the'ring is arranged concentrically with the bore of said spindle casing.

and a groove formed in the inner face of the other of said posts, a pair of washers mounted upon said posts, the bore of said washers being eccentric to the circumference thereof, an eccentric washer mounted intermediate said washers and between said posts, a ring having a central bore arranged about said post, the bore of said ring slidably receiving said first named washers, an annular groove formed in the interior of said ring, an extension of said eccentric washer adapted to enter said groove when the bore of the washer is alined with the bore of said spindle casing the lug of said first mentioned post being adapted to engage in the groove in said ringwhen the ring is arranged concentrically with the bore of said spindle casing.

10. In a micrometer gage, the combinaof said posts and a groove formed the inner face of the other of said posts, a pair of washers mountedupon said posts, an eccentrlc washer mounted intermediate said washers and between said posts and enter ing the groove in said last-named post, a ring having a central bore of greater diameter than the distance between the outside faces of said posts arranged about said posts, an annular groove formed in the interior of said ring, an extension on said eccentric washer adapted to enter said groove when the bore of the washer is alined with the bore of said spindle casing the lug of said first-mentioned post being adapted to engage in the groove in said ring when said ring is arranged concentrically with the bore of said spindle casing, and means operated by the rotation of said ring for shifting said eccentric washer.

In testimony whereof I afiix my signature in presence of two witnesses.

r JAMES E. HASTINGS. W'itnesses:

CHARLES W. FAULKNEB, WILLIAM H. ALLEN. 

